In this guide, "spatial analysis" is understood to refer to any analysis that aims to detect spatial structuring in response data. This is distinct from the simple incorporation of spatial variables (such as latitude and longitude data) into an analysis. Spatial structures can generally be attributed to either spatial autocorrelation or to forcing (i.e. the effect of one or more explanatory variables over a spatial gradient). As it is unlikely that all response variables will be controlled by the same spatial influences, different response variables (e.g. OTU abundances) may show spatial structuring at different scales. Further, any given response variable can show different spatial structures at several scales. |